Service providers and device manufacturers (e.g., wireless, cellular, etc.) are continually challenged to deliver value and convenience to consumers by, for example, providing compelling network services. One area of interest involves system performance in 60 GHz communication systems. According to current 60 GHz communication standards such as the Wireless Gigabit Alliance (WiGig), a data packet format that is communicated between at least two devices has information such as a program number, a sequence number, program clock reference (PCR) value, variable delay reference (VDR) value and a flag. WiGig requires that each data packet carries a PCR value that contains a timestamp (i.e., counter value) corresponding to a 27 MHz video clock. According to some implementations, this video clock resides in a graphics processing unit (GPU) and the PCR value is generated by the GPU by way of a display engine. The data packet also contains a VDR value which captures the delay variation for each packet. The VDR is the variable queuing time for each data packet.
Conventionally, the VDR value is determined based on the PCR value. There may be instances where the PCR value is inaccurate for example due to the fact that the display engine cannot generate accurate PCR value fast enough for every packet since the processing load is too high. The inaccurate PCR value, in turn, results in an inaccurate VDR value. An inaccurate VDR value often results in increased clock jitter and increased clock acquisition time at the receiver, which leads to an unsatisfactory user experience.
In addition, a packet may be retransmitted in wireless link and there are two possibilities to handle the VDR value when retransmission happens. If the VDR is not re-calculated, then the VDR value becomes inaccurate. An inaccurate VDR value results in increased clock jitter and increased clock acquisition time at the receiver, which leads to unsatisfactory user experience. If VDR value is re-calculated when retransmission happens, it results in a mismatch between the sequence number value and the packet number value from the encryption process. As such, the data packet will be dropped at a receiver side of a radio communication because of this mismatch. This dropping degrades the performance of the delivered service.